National FIA Field Guide
Draft Version 8/99
FOREST INVENTORY AND ANALYSIS
NATIONAL CORE FIELD GUIDE
VOLUME I: FIELD DATA COLLECTION PROCEDURES FOR PHASE 2 PLOTS
Version 1.3
Version History:
1.1: March 1999
1.2: August 1999 (first version implemented, Maine, 1999)
1.3: September 1999 (revised from Bangor Data Band meeting)
INTRODUCTION
This document describes standards, codes, methods, and definitions for National Forest
Inventory and Analysis (FIA) field data items. The objective is to describe core FIA field
procedures that will be consistent and uniform across all FIA units. This core serves as
the framework for regional FIA programs; individual programs may add variables,
but may not change the core requirements. Unless otherwise noted, the items in this
manual are considered CORE, that is, the information will be collected by all FIA Units as
specified. Items or codes specified as CORE OPTIONAL are not required by individual
units; however, if the item is collected or coded, it will be as specified in this manual. It is
expected that all items in this Volume can be measured by a two person crew in less than
a single day, on average, including time spent walking to and from the plot.
The FIA program is in transition, changing in response to legislation and new customer
demands. One of these demands is for increased consistency, which this manual begins
to address. Another change will be the merger of the FIA program with the plot
component of the Forest Health Monitoring (FHM) program. This will be accomplished by
a joint sampling approach where FHM plots become a subset of the larger sample of FIA
plots. In this model, plots formerly known as FIA plots will now be called Phase 2 plots;
plots formerly known as FHM will be called Phase 3 plots.
The focus of Volume I is on data that are collected in the field on all Phase 2 plots in the
FIA sample. Volume II of the series will describe an expanded suite of data collected on
the phase 3 sub-sample. Volume II will consist of the FHM field manual, minus data
elements already collected on the FIA sample. Volume III of the series (in preparation)
will document the office procedures including data elements measured in the office, data
from other sources that are merged into the FIA database, and core compilation and
analysis algorithms. When complete, the three volume set will describe all data
measured consistently across the country and comprising the core FIA program.
FIELD GUIDE LAYOUT
Each section of the field guide corresponds to one of the following sections:
0 General description
1 Plot
2 Condition
3 Boundary
4 Subplot
5 Tree measurements
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6 Seedling
7 Site Tree
8 Non Forest/Access Denied plots
Each section begins with some general overview of the data elements collected at that
level, along with whatever technical background is necessary to prepare the field crews
for data collection. Descriptions of data elements follow, in the following format:
DATA ELEMENT NAME --
Field width: X digits
MQO:
Values:
Field width designates the number of columns (or spaces) needed to properly record the
data element. Measurement Quality Objective (MQO) describes the acceptable tolerance
for each data element. MQOs consist of two parts: a statement of the tolerance, and a
percentage of time where the collected data are required to be within tolerance.
Tolerances may be stated in terms of + or - a number of classes for ordered categorical
data elements (e.g. + or - 2 classes); in absolute terms for some continuous variables
(e.g. + or - 0.2 inches); or in terms of percent of the value of the data element (e.g., + or -
10% of the value). For some data elements, no errors are tolerated (e.g., plot ID
number).
Percentage of time within tolerance is generally expressed as "at least X percent of the
time," meaning that crews are expected to be within tolerance at least X percent of the
time.
UNITS OF MEASURE
The field guide will use ENGLISH as the primary unit system..
Plot Dimensions:
Annular plot -- for sample intensification or sampling relatively rare events.
Radius = 59.0 ft.
Area = 10,935.88 sq. ft. or 0.25 ac.
Subplot - for selecting trees with diameter ³ 5.0 in.
Radius = 24.0 ft.
Area = 1,809.56 sq. ft. or 0.04 ac.
Microplot - for selecting seedlings and saplings
Radius = 6.8 ft.
Area = 145.27 sq. ft. or 0.003 ac.
Distance between subplots is 120.0 ft.
The minimum area needed to qualify as forest land is 1.0 acre.
The minimum width to qualify as forest land is 120.0 ft.
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Tree Limiting Dimensions:
English
breast height 4.5 ft.
stump height 1.0 ft.
merchantable top 4.0 in.
minimum conifer seedling height 6.0 in.
minimum hardwood seedling height 12.0 in.
seedling/sapling DBH/DRC break 1.0 in.
sapling/tree DBH/DRC break 5.0 in.
softwood large/medium DBH break 9.0 in.
hardwood large/medium DBH break 11.0 in.
western woodland large/med. DRC break 9.0 in.
0.0 GENERAL DESCRIPTION
The CORE field plot consists of four subplots approximately 1/24 ac. with a 24.0 ft. radius
. The center subplot is subplot 1. Subplots 2, 3, and 4 are located 120.0 ft. at azimuths
of 360, 120, and 240 degrees from the center of subplot 1. Subplots are used to collect
data on trees with a diameter at breast height (DBH) (or diameter at root collar (DRC) for
western woodland species) of 5.0 in. or greater. Throughout this manual, use of the word
'plot' refers to the entire set of four subplots. “Plot Center” is defined as the center of
subplot 1.
Each subplot contains a microplot of approximately 1/300 ac. with a radius 6.8 ft. . The
center of the microplot is offset 90 degrees and 12.0 ft. from plot center. Microplots are
numbered in the same way as subplots. Microplots are used to select and collect data on
saplings (DBH/DRC of 1.0 in. to 4.9 in.) and seedlings (DBH/DRC less than 1.0 in.).
As a CORE OPTION, the field plot may also include annular plots of approximately 1/4
ac. with radius 59.0 ft. with the annular plot center coinciding with the subplot center.
Annular plots are numbered in the same way as subplots. Annular plots may be used to
select and collect additional data for regional enhancements, for example to provide a
better sample of rare population elements such as very large trees.
Data are collected on each field plot at the following levels:
Plot Data that describe the entire cluster of four subplots.
Subplot Data that describe a single subplot of a cluster.
Condition Class A discrete combination of landscape attributes that describe the
environment on all or part of the plot. Examples of such
attributes include condition status, forest type, stand size, stand
origin, owner group, reserved status, and tree density.
Boundary An approximate description of the demarcation line between two
condition classes that occur on a single subplot, microplot, or
annular plot. There is no boundary recorded when the
demarcation occurs beyond the fixed radius plots.
Tree Data describing saplings with diameter 1.0 in. to 4.9 in., and trees
with diameter ³ 5.0 in..
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Seedling Data describing trees with diameter 5 years
Values: 1999 or higher
3.0 BOUNDARY REFERENCES
Boundary reference data are used to remeasure plots and to compute the area for the
condition classes sampled on a plot. Record all boundaries between condition classes
that occur within the sampled (fixed-radius) area on subplots and microplots (and
optionally annular plots). Boundaries outside sampled (fixed-radius) areas are not
referenced.
In addition to the recording procedures described herein, sketch maps of condition class
boundaries onto the pre-printed plot diagrams on field tally sheets.
3.1 REFERENCE PROCEDURE -- Reference, within the sampled area on each microplot,
subplot, and annular plot, the approximate boundary of each condition class that differs
from the condition class at a subplot center. Trees selected on these fixed-radius plots
are assigned to the actual condition in which they lie regardless of the recorded
approximate boundary.
Boundary referencing is done by recording azimuths and distances from subplot center to
the reference points. Each boundary is marked by a maximum of three points -- two
where the boundary intersects the subplot circumference, and one "corner" point between
the two end points, if necessary. Only the corner point requires a distance, since the
distance from the center to the circumference is always equal to the fixed plot radius.
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boundary
right azimuth 030 degrees
Condition 2
Condition 1
left azimuth 225 degrees
boundary
boundary
left azimuth
335 degrees
Condition 1 corner distance 12 ft.
corner azimuth 90 degrees
Condition 2
right azimuth
220 degrees
boundary
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Microplot boundaries are referenced to the microplot center, and annular plot boundaries
are referenced to the subplot center in the same manner described for subplots. Note
that the larger the plot, the greater likelihood of a need for a boundary corner to record
boundaries that are not straight lines.
Refer to 2.1 for general mapping guidelines. The following additional rules apply when
referencing a boundary within a subplot, microplot, or annular plot:
1 When a boundary between forest land and nonforest land or between two
contrasting forest land conditions is clearly marked, use that feature to define
the boundary. Examples of clear demarcation are a fence line, plowed field
edge, sharp ridge line, and water's edge along a stream course, ditch, or
canal.
2 When a boundary between forest land and nonforest land is not marked by
an obvious feature, the boundary should follow the nonforest side of the
stems of the trees at the forest edge.
3 When a boundary between two contrasting forest land conditions is not
clearly marked, map along the stems of the contrasting condition. When the
boundary between two contrasting forest land conditions is separated by a
narrow linear inclusion (creek, fire line, narrow meadow, unimproved road),
establish the boundary at the far edge, relative to subplot center, of the
inclusion.
4 When a plot is remeasured, the crew will examine the boundaries referenced
at last inventory. If no change has occurred, the current crew will retain the
downloaded boundary data that was recorded at last inventory. If boundary
has changed, or a new boundary is present, or the previous crew made an
obvious error, record new or updated boundary data. Delete boundaries no
longer distinct.
5 Although individual measurement quality objectives are specified for the
azimuths and distances, in practice a crew will be considered „correct‟ when
the difference in areas as mapped by the original crew and by the QA crew is
less than 10% of the subplot or microplot area. This allows for slight
variations in azimuths or distances due to the approximate nature of our
mapping procedures. This area check should be programmed into the field
data recorders and used to determine pass or failure for QA purposes.
3.2 BOUNDARY DATA -- Record the appropriate values for each boundary mapped on the
subplot, microplot, or annular plot, as follows:
3.2.1 SUBPLOT NUMBER -- Record the code corresponding to the number of the subplot.
When collected: All boundaries
Field width: 1 digit
MQO: No errors, 100% of time
Values:
1 center subplot
2 north subplot
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3 southeast subplot
4 southwest subplot
3.2.2 PLOT TYPE -- Specify whether the boundary data is for a subplot, microplot, or annular
plot.
When collected: All boundaries
Field width: 1 digit
MQO: No errors 100% of time
Values:
1 subplot boundary
2 microplot boundary
3 annular plot boundary (coded only when annular plots are taken)
3.2.3 BOUNDARY CHANGE -- (Remeasurement locations only). Record the appropriate code
to indicate if the data for a boundary are being copied from the previous crew's data.
When collected: All boundaries
Field width: 1 digit
MQO: No errors 100% of time
Values:
0 No change -- boundary is the same as indicated on the plot map.
1 Boundary has been changed to reflect a difference(s) from the
boundaries recorded, if any, at last visit.
2 Boundary has been changed to correct an error from previous crew.
3 Boundary has been changed to reflect a change in variable definition.
3.2.4 CONTRASTING CONDITION -- Record the condition class that contrasts with the
condition class located at the subplot center (e.g., the condition class on the other side of
the boundary line).
When collected: All boundaries
Field width: 1 digit
MQO: No errors 100% of time
Values:
1 Condition Class 1
2 Condition Class 2
.
.
.
9 Condition Class 9
3.2.5 LEFT AZIMUTH -- Record the azimuth to the farthest left point (facing the contrasting
condition) where the boundary intersects the subplot, microplot, or annular plot
circumference.
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When collected: All boundaries
Field width: 3 digits
MQO: +/- 10 degrees, at least 90% of time
Values: 001 to 360
3.2.6 CORNER AZIMUTH -- Record the azimuth from the subplot center to a corner or curve in
a boundary. If a boundary is best described by a straight line between the two
circumference points, then record 000 for corner azimuth (000=none).
When collected: All boundaries
Field width: 3 digits
MQO: +/- 10 degrees, at least 90% of time
Values: 000 to 360
3.2.7 CORNER DISTANCE -- Record the horizontal distance, to nearest 1 ft., from the subplot
center to a boundary corner point.
When collected: All boundaries
Field width: 2 digits
MQO: +/- 1 ft., at least 90% of time
Values:
microplot 1 to 6 ft.
subplot 1 to 24 ft.
annular plot 1 to 59 ft.
3.2.8 RIGHT AZIMUTH -- Record the azimuth to the farthest right point (facing the contrasting
condition) where the boundary intersects the subplot, microplot, or annular plot
circumference.
When collected: All boundaries
Field width: 3 digits
MQO: +/- 10 degrees, at least 90% of time
Values: 001 to 360
4.0 SUBPLOT INFORMATION
Each subplot is described by a series of area parameters relating to topographic features
and existing cover type. These data also relate to the microplot, since the microplot is
contained within the subplot perimeter.
4.1 SUBPLOT NUMBER -- Record the code corresponding to the number of the subplot
When Collected: All subplots.
Field width: 1 digit
MQO: No errors, 100% of time
Values:
1 center subplot
2 north subplot
3 southeast subplot
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4 southwest subplot
4.2 SUBPLOT CENTER CONDITION -- Record the condition class at the subplot center.
Use the same procedures described for Contrasting Condition number in Section 3.2.4.
When collected: All subplots
4.3 MICROPLOT CENTER CONDITION -- Record the condition class at the microplot center.
Use the same procedures described for Contrasting Condition number in Section 3.2.4.
When collected: All microplots
4.4 SUBPLOT SLOPE -- Record the angle of slope of the condition to the nearest 1 percent.
Percent Slope is determined by sighting the clinometer along a line parallel to the average
incline (or decline) of each subplot. This angle is measured along the shortest pathway
down slope before the drainage direction changes. To measure Percent Slope, Observer
1 should stand at the uphill edge of the subplot and sight Observer 2, who stands at the
downhill edge of the subplot. Sight Observer 2 at the same height as the eye-level of
Observer 1. Read the slope directly from the percent scale of the clinometer
If slope changes gradually across the subplot, record an average slope. If slope changes
across the subplot but the slope is predominately of one direction, code the predominate
slope percentage rather than the average. If the subplot falls on or straddles a canyon
bottom or narrow ridge top code slope as follows:
· Code the average slope of the side hill(s).
· If subplot falls on a canyon bottom or on a narrow ridge top, but most of the area
lies on one side hill, code the slope of the side hill.
When collected: All subplots
Field width: 3 digits
MQO: +/- 10%, at least 90% of the time
Values: 000 TO 155 percent slope
4.5 SUBPLOT ASPECT -- Record the aspect, to the nearest 1 degree. Aspect is determined
along the direction of slope for land surfaces with at least 5 percent slope in a generally
uniform direction. Aspect is measured with a hand compass along the same direction
used to determine slope. If aspect changes gradually across the subplot, record an
average aspect. If aspect changes across the subplot but the aspect is predominately of
one direction, code the predominate direction rather than the average.
If the subplot falls on or straddles a canyon bottom or narrow ridge top code aspect as
follows:
· Code the aspect of the ridge line or canyon bottom.
· If subplot falls on a canyon bottom or on a narrow ridge top, but most of the area
lies on one side hill, code the aspect of the side hill.
When collected: All subplots
Field width: 3 digits
MQO: +/- 10 degrees, at least 90% of time
Values:
000 no aspect, slope = 5 in. DBH) or microplot center (for trees = 5 in. DBH) or microplot center (for trees 5.0 in.):
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5.11 PERCENT ROTTEN/MISSING CULL -- Record the percent rotten or missing cubic-foot
cull for all tally trees, live and dead.
When Collected: All tally trees
Field width: 2 digits
MQO: +/- 10%, at least 90% of the time
Values: 0 to 99
For each tally tree 5.0-inch DBH/DRC and larger, record the percentage of rotten and
missing cubic-foot volume, to the nearest 5 percent. When estimating volume loss (tree
cull) only consider the cull on the merchantable bole/portion of the tree, from a 1 ft. stump
to a 4 inch top.
Rotten and missing volume loss is often difficult to estimate. Refer to supplemental
disease and insect pests field guides and local defect guidelines as an aid in identifying
damaging agents and their impact on volume loss. Use your best judgment and be alert
to such defect indicators as the following:
· Cankers or fruiting bodies.
· Swollen or punky knots.
· Dull, hollow sound of bole when struck with an ax.
· Large dead limbs, esp. those with frayed ends.
· Sawdust around the base of the tree.
5.12 TOTAL LENGTH -- Record the total length of the tree, to the nearest 1.0 ft. from ground
level to the tip of the apical meristem. For trees growing on a slope, measure on the
uphill side of the tree. If the tree has a broken or missing top, estimate what the total
length would be if there were no missing or broken top. Forked trees should be treated
the same as unforked trees.
When Collected: All tally trees
Field width: 3 digits
MQO: +/- 10% of true length, at least 90% of the time
Values: 005 to 400
5.13 ACTUAL LENGTH – For trees with broken or missing tops. Record the actual length of
the tree from ground level to the highest remaining portion of the tree still present and
attached to the bole. I If the top is intact, this item may be omitted. Forked trees should
be treated the same as unforked trees.
When Collected: All tally trees
Field width: 3 digits
MQO: +/- 10% of true length, at least 90% of the time
Values: 005 to 400
5.14 LENGTH METHOD -- Record the code that indicates the method used to determine tree
length.
When Collected: All tally trees
Field width: 1 digit
MQO: No errors, 100% of time
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Values:
1 Total and actual lengths are field measured with a measurement
instrument (e.g., clinometer, relascope)
2 Total length is visually estimated, actual length is measured with an
instrument.
3 Total and actual lengths are visually estimated.
5.15 CROWN CLASS -- Rate tree crowns in relation to the sunlight received and proximity to
neighboring trees. Base the assessment on the position of the crown at the time of
observation, regardless of the past history. Example: a formerly suppressed tree which
is now dominant due to tree removal is classed as dominant.
When Collected: All live tally trees
Field width: 1 digit
MQO: No errors, at least 85% of the time
Values:
1 Open Grown: Trees with crowns that received full light from above and
from all sides throughout most of its life, particularly during its early
developmental period.
2 Dominant: Trees with crown extending above the general level of the
crown cover and receiving full light from above and partly from the sides.
These trees are taller than the average trees in the stand and their
crowns are well developed, but they could be somewhat crowded on the
sides.
Also, trees whose crowns have received full light from above and from all
sides during early development and most of their life. Their crown form or
shape appears to be free of influence from neighboring trees.
3 Co-dominant: Trees with crowns at the general level of the crown
canopy. Crowns receive full light from above but little direct sunlight
penetrates their sides. Usually they have medium-sized crowns and are
somewhat crowded from the sides. In stagnated stands, co-dominant
trees have small-sized crowns and are crowded on the sides.
4 Intermediate: These trees are shorter than dominants and co-dominant,
but their crowns extend into the canopy of co-dominant and dominant
trees. They receive little direct light from above and none from the sides.
As a result, intermediates usually have small crowns and are very
crowded from the sides.
5 Overtopped: Trees with crowns entirely below the general level of the
crown canopy that receive no direct sunlight either from above or the
sides.
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2 5 3 2 4 3 3 2 5 2 1
5.16 COMPACTED CROWN RATIO -- Record the compacted crown ratio for each live tally
tree, 1.0 in. and larger. Crown ratio is that portion of the tree supporting live foliage and is
expressed as a percentage of the actual tree height. To determine compacted crown
ratio, ocularly transfer lower live branches to fill in large holes in the upper portion of the
tree until a full, even crown is visualized.
When Collected: All live tally trees
Field width: 3 digits
MQO: +/- 10%, at least 80% of the time
Values: 00 to 99 percent
5.17 TREE DAMAGE -- Damage is characterized according to three attributes: location of
damage, type of damage, and severity of damage. Up to three different damages can be
recorded per tree. Damages must meet severity thresholds (defined in section 5.17.3,
DAMAGE SEVERITY) in order to be recorded.
The tree is observed from all sides starting at the roots. Damage signs and symptoms
are prioritized and recorded based on location in the following order: roots, roots and
lower bole, lower bole, lower and upper bole, upper bole, crownstem, and branches
recorded as location code 0 (for no damage), or DAMAGE LOCATION 1-7.
Within any given location, the hierarchy of damage follows the numeric order of DAMAGE
TYPE possible for that location. The numeric order denotes decreasing significance as
the code number goes up, i.e., DAMAGE TYPE 01 is more significant than DAMAGE
TYPE 25. A maximum of three damages are recorded for each tree. If a tree has more
than three damages that meet the threshold levels, the first three that are observed
starting at the roots are recorded.
When multiple damages occur in the same place, the most damaging is recorded. For
example, if a canker, DAMAGE TYPE 02, meets the threshold and has a conk growing in
it, record only the canker. Another example is, if an open wound meets threshold and
also has resinosis, record only the open wound.
5.17.1 DAMAGE LOCATION 1 -- This is the location on the tree where DAMAGE TYPE 1 is
found. If the same damage continues into two or more locations, record the appropriate
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code listed below, or if the combination of locations does not exist (damage extends from
crownstem to roots), record the lowest location that best describes the damage (see
Figure 3-2). Multiple damages may occur in the same location, but record the higher
priority damage (lower code number) first. If the damages are coincident (a conk within a
canker), record only the higher priority damage.
The “base of the live crown” is defined as the horizontal line which would touch the lowest
part of the foliage, excluding branches towards the base of the tree which are less than
1.0 inch or more than 5 feet from the rest of the crown
When Collected: All live tally trees
Field width: 1 digits
MQO: +/- 1, at least 80% of the time
Values:
0 No damage
1 Roots (exposed) and stump (12 inches in height from ground level)
2 Roots, stump, and lower bole
3 Lower bole (lower half of the trunk between the stump and base of the
live crown)
4 Lower and upper bole
5 Upper bole (upper half of the trunk between stump and base of the live
crown)
6 Crownstem (main stem within the live crown area, above the base of the
live crown)
7 Branches (>1 in. at the point of attachment to the main crown stem within
the live crown area)
5.17.2 DAMAGE TYPE 1 -- This is the first damage observed that meets the damage threshold
definition in the lowest location. Damage categories are recorded based on the numeric
order that denotes decreasing significance from damage 01 - 31.
When Collected: All live tally trees
Field width: 2 digits
MQO: No errors, at least 80% of the time
Values:
1 Canker, gall: Cankers may be caused by various agents but are most
often caused by fungi. The bark and cambium are killed, and this is
followed by death of the underlying wood, although the causal agent may
or may not penetrate the wood. This results in areas of dead tissue that
become deeper and wider, or galling (including galls caused by rusts), on
roots, bole, or branches. Due to the difficulty in distinguishing some
abnormal swellings (e.g. burls) from classic galls and cankers, all are
recorded as damage 01. A canker may be:
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Annual (enlarges only once and does so within an interval briefer than the growth
cycle of the tree, usually less than one year),
Diffuse (enlarges without characteristic shape or noticeable callus formation at
margins), or
Perennial (enlarges during more than one year -- often has a target appearance).
2 Conks, fruiting bodies, and signs of advanced decay: Fruiting bodies on the main
bole, crownstem, and at the point of the branch attachment are signs of decay.
"Punky wood" is a sign of decay and is evidenced by soft, often moist, and
degraded tissue.
Cavities into the main bole that are oriented in such a way that they act as
catchment basins for water are signs of decay. Bird cavities are signs of decay.
Rotten branches or branches with conks are not indicators of decay unless the
threshold is met (>20% of branches are affected).
Rotting stumps associated with coppice regeneration (e.g., northern pin oak,
maple) are excluded from coding.
3 Open wounds: An opening or series of openings where bark has been removed
or the inner wood has been exposed and no signs of advanced decay are
present. Improper pruning wounds that cut into the wood of the main stem are
coded as open wounds, if they meet the threshold; those which leave the main
stemwood intact are excluded.
4 Resinosis or gummosis: The origin of areas of resin or gum (sap) exudation on
branches and trunks.
5 Cracks and seams: Cracks in trees are separations along the radial plane.
When they break out to the surface they often are called frost cracks. These
cracks are not caused by frost or freezing temperature, though frost can be a
major factor in their continued development. Cracks are most often caused by
basal wounds or sprout stubs, and expand when temperatures drop rapidly.
Seams develop as the tree attempts to seal the crack, although trees have no
mechanism to compartmentalize this injury.
Lightning strikes are recorded as cracks when they do not meet the threshold for
open wounds.
11 Broken bole or roots less than 3 feetfrom bole: Broken roots within 3 feetof bole
either from excavation or rootsprung for any reason. For example, those which
have been excavated in a road cut or by animals.
Stem broken in the bole area (below the base of the live crown) and tree is still
alive.
12 Brooms on roots or bole: Clustering of foliage about a common point on the
trunk. Examples include ash yellows witches' brooms on white and green ash
and eastern and western conifers infected with dwarf mistletoes.
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13 Broken or dead roots (beyond 3 feet): Roots beyond 3 feetof bole that are broken
or dead.
20 Vines in the crown: Kudzu, grapevine, ivy, dodder, etc. smothers tree crowns.
Vines are rated as a percentage of tree crown affected.
21 Loss of apical dominance, dead terminal: Mortality of the terminal of the
crownstem caused by frost, insect, pathogen, or other causes.
22 Broken or dead: Branches that are broken or dead. Snag branches (those with
no twigs) are ignored and not coded as dead. Dead or broken branches attached
to the bole or crownstem outside the live crown area are not coded. 20% of the
main, first order portion of a branch must be broken for a branch to be coded as
such.
23 Excessive branching or brooms within the live crown area: Brooms are a dense
clustering of twigs or branches arising from a common point that occur within the
live crown area. Includes abnormal clustering of vegetative structures and
organs. This includes witches' brooms caused by ash yellows on green and white
ash and those caused by dwarf mistletoes.
31 Other: Use when no other explanation is appropriate. Specify in comments
section of PDR for "tree notes." Code 31 is used to maintain consistency with the
phase 3 crown damage protocols.
Legal Combinations of DAMAGE TYPE by DAMAGE LOCATION:
For each of the following location codes, possible damage codes and damage definitions
are presented. Minimum damage thresholds are described in Section 5.17.3, DAMAGE
SEVERITY.
Location 1: Roots and stump
01 Canker, gall -- exceeds 20% of circumference of stump
02 Conks, fruiting bodies, and signs of advanced decay -- any occurrence
03 Open wounds -- exceeds 20% of circumference of stump
04 Resinosis or gummosis -- origin of flow width exceeds 20% of
circumference of stump
05 Cracks and seams -- any occurrence
11 Broken bole or roots less than 3 feet from bole -- any occurrence
12 Brooms on roots or bole -- any occurrence.
13 Broken or dead roots -- exceeds 20% of roots, beyond 3 feet of bole,
broken or dead
31 Other
Location 2: Roots, stump, and lower bole
01 Canker, gall -- exceeds 20% of circumference of stump
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02 Conks, fruiting bodies, and signs of advanced decay -- any occurrence
03 Open wounds – exceeds 20% at the point of occurrence, or for the
portion in root zone, 20% of the circumference of stump
04 Resinosis or gummosis -- origin of flow width exceeds 20% at the point of
occurrence, or for the portion in root zone, 20% of circumference of
stump.
05 Cracks and seams - any occurrence
11 Broken bole or roots less than 3 feet from bole -- any occurrence
12 Brooms on roots or bole - -any occurrence.
13 Broken or dead roots -- exceeds 20% of roots, beyond 3 feet of bole,
broken or dead
31 Other
Location 3: Lower bole
01 Canker, gall -- exceeds 20% of circumference at the point of occurrence
02 Conks, fruiting bodies, and signs of advanced decay -- any occurrence
03 Open wounds -- exceeds 20% of circumference at the point of
occurrence
04 Resinosis or gummosis -- origin of flow width exceeds 20% of
circumference at the point of occurrence
05 Cracks and seams -- any occurrence
11 Broken bole or roots less than 3 feet from bole -- any occurrence
12 Brooms on roots or bole -- any occurrence
31 Other
Location 4: Lower and upper bole -- same as lower bole.
Location 5: Upper bole - same as lower bole.
Location 6: Crownstem
01 Canker, gall -- exceeds 20% of circumference of crownstem at the point
of occurrence
02 Conks, fruiting bodies, and signs of advanced decay -- any occurrence
03 Open wounds - exceeds 20% of circumference at the point of occurrence
-- any occurrence
04 Resinosis or gummosis -- origin of flow width exceeds 20% of
circumference at the point of occurrence
05 Cracks and seams -- all woody locations -- any occurrence.
31 Other
Location 7: Branches >1 in. at the point of attachment to the main or crown stem
01 Canker, gall -- exceeds 20% of circumference on at least 20% of
branches
02 Conks, fruiting bodies and signs of advanced decay -- more than 20% of
branches affected
03 Open wounds -- exceeds 20% of circumference at the point of
occurrence on at least 20% of branches
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04 Resinosis or gummosis -- origin of flow width exceeds 20% of
circumference at the point of occurrence on at least 20% of branches
05 Cracks and seams -- all occurrences, and on at least 20% of branches
20 Vines in the crown -- more than 20% of live crown affected
22 Broken or dead -- more than 20% of branches affected within the live
crown area
23 Excessive branching or brooms -- more than 20% of branches affected
31 Other
5.17.3 DAMAGE SEVERITY 1 -- This is the amount of affected area (above threshold) in
DAMAGE LOCATION 1 recorded for TREE DAMAGE1. Severity codes vary depending
on the type of damage recorded.
When Collected: All live tally trees
Field width: 2 digits
MQO: No errors, at least 80% of the time
Values: The codes and procedures for SEVERITY 1 values are defined for each
DAMAGE TYPE 1.
DAMAGE TYPE Code 01 -- Canker, gall
Measure the affected area from the margins (outer edges) of the canker or gall within any
3 foot vertical section in which at least 20% of circumference is affected at the point of
occurrence. For location 7, and location 1, 20% of branches and roots beyond 3 feet,
respectively, must be affected, then record in 10% classes. See Figure 3-3.
Severity classes for code 01 (percent of circumference affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 02 -- Conks, fruiting bodies, and signs of advanced decay
Severity classes for code 02: None. Enter code 0 regardless of severity, except for roots > 3 ft.
from the bole, or number of branches affected - 20%
DAMAGE TYPE Code 03 -- Open wounds
The damaged area is measured at the widest point between the margins of the exposed
wood within any 3 foot vertical section in which at least 20% of the circumference is
affected at the point of occurrence. For location 7, and location 1, 20% of branches and
roots beyond 3 feet, respectively, must be affected, then record in 10% classes. See
Figure 3-4.
Severity Classes for code 03 (percent of circumference affected):
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Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 04 -- Resinosis or gummosis
Resinosis or gummosis is measured at the widest point of the origin of the flow width in
which at least 20% of the circumference is affected at the point of occurrence. For
location 7, and location 1, 20% of branches and roots beyond 3 feet, respectively, must
be affected, then record in 10% classes.
Severity classes for code 04 (percent of circumference affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 05 -- Cracks and seams
Severity class for code 05
Record "0" for the lowest location in which the crack occurs. For location 7, and location
1, 20% of branches and roots beyond 3 feet, respectively, must be affected, then record
in 10% classes.
DAMAGE TYPE Code 11 -- Broken bole or roots less than 3 feet from bole
Severity classes for code 11: None. Enter code 0 regardless of severity.
DAMAGE TYPE Code 12 -- Brooms on roots or bole
Severity classes for code 12: None. Enter code 0 regardless of severity.
DAMAGE TYPE Code 13 -- Broken or dead roots
At least 20% of roots beyond 3 feet of bole that are broken or dead.
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Severity classes for code 13 (percent of roots affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 20 -- Vines in crown
Severity classes for code 20 (percent of live crown affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 21 -- Loss of apical dominance, dead terminal
Any occurrence ( > 1%) is recorded in 10% classes as a percent of the crownstem
affected. Use trees of the same species and general DBH class in the area or look for
the detached portion of crownstem on the ground to aid in estimating percent affected. If
a lateral branch has assumed the leader and is above where the previous terminal was,
then no damage is recorded.
Severity classes for code 21:
Classes Code
01-09 0
10-19 1
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 22 -- Broken or dead branches ( >1in. above the swelling at the point of
attachment to the main or crown stem within the live crown area)
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At least 20% of branches are broken or dead.
Severity classes for code 22 (percent of branches affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 23 -- Excessive branching or brooms
At least 20% of crownstem or branches affected with excessive branching or brooms.
Severity classes for code 23 (percent of area affected):
Classes Code
20-29 2
30-39 3
40-49 4
50-59 5
60-69 6
70-79 7
80-89 8
90-99 9
DAMAGE TYPE Code 31 -- Other
Severity classes for code 31:
None. Enter code 0 regardless of severity. Describe condition in notes.
Procedures to Record Multiple Occurrences of the Same Damage
Damage codes 01 (canker), 03 (open wounds), and 04 (resinosis/gummosis) must meet
a threshold of 20 percent of the circumference at the point of occurrence, within any 3 ft.
section. Multiple cankers or open wounds which are directly above one another pose no
more threat to long term tree survival than would a single damage incidence of the same
width. However, should multiple damages be located horizontally within any 3 foot
section, the translocation of water and nutrients would be significantly affected. The
widths of each individual damage are added and compared as a percent, to the total
circumference at the midpoint of the 3 foot section (Figure 3-2).
Procedures to Measure Circumference Affected
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A practical approach is to observe every face of the "stump", bole, or crownstem. About
40% of the circumference of a face can be observed at any one time. The damage is
measured horizontally between the margins. If the cumulative area affected within a 3
foot section exceeds 1/2 of any face, then the 20% minimum threshold has been met.
The percent of the circumference affected by damage is then estimated in 10% classes.
If in doubt, measure the damage and circumference at the widest point of occurrence on
the bole with a linear tape, and determine the % affected.
5.17.4 DAMAGE LOCATION 2 -- This is the location on the tree where TREE DAMAGE 2 is
found. Follow the same procedures as for DAMAGE LOCATION 1.
5.17.5 DAMAGE TYPE 2 -- This is the second damage observed that meets the damage
threshold definition in the lowest location. Follow the same procedures as for DAMAGE
TYPE 1.
5.17.6 DAMAGE SEVERITY 2 -- This is the amount of affected area (above threshold) in
DAMAGE LOCATION 2 recorded for DAMAGE TYPE 2. Follow the same procedures as
for DAMAGE SEVERITY 1
5.18 CAUSE OF DEATH -- Record a cause of death for all trees that have died or been cut
since the previous survey. If cause of death cannot be reliably estimated, record
unknown/not sure.
When Collected: All trees which were live tally trees at the previous measure and are
now dead.
Field width: 2 digits
MQO: at least 80% agreement
Values:
10 Insect damage
20 Disease damage
30 Fire damage
40 Animal damage
50 Weather damage
60 Vegetation (suppression, competition, vines/kudzu)
70 Unknown/not sure/other (include notes)
80 Human-caused damage (cultural, logging, accidental damage, etc.)
90 Physical (hit by falling tree)
5.19 MORTALITY YEAR – Record the estimated year that remeasured trees died. For each
downloaded tree that has died or been cut since the previous inventory, record the 4-digit
year in which the tree died. Mortality year is also recorded for trees on land that has been
diverted to a nonforest land use, if it can be determined that a tree died before the land
was diverted.
When Collected: All trees which were live tally trees at the previous measure and are
dead at the current measure.
Field width: 4 digits
MQO: +/- 1 years, 70% of the time for remeasurement cycles of 5 years
+/- 2 years, 70% of the time for remeasurement cycles of > 5 years
Values: 1999 or higher
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5.20 DECAY CLASS -- record for each standing dead tree, 5.0-inch in diameter and larger,
indicating the trees stage of decay.
When Collected: All dead tally trees.
Field width: 1 digit
MQO: ±1 class, at least 90% of the time.
Values: Use the following table for guidelines:
Sapwood
Decay Limbs and % Bark presence Heartwood
*
stage branches Top Remaining and condition
*
(code) condition
All present Pointed 100% Intact; sound, Sound, hard,
1 incipient original color
decay, hard,
original color
2 Few limbs, no May be Variable Sloughing; Sound at base,
fine branches broken advanced incipient decay in
decay, outer edge of upper
fibrous, firm bole, hard, light to
to soft, light reddish brown
brown
3 Limb stubs Broken Variable Sloughing; Incipient decay at
only fibrous, soft, base, advanced
light to decay throughout
reddish upper bole, fibrous,
brown hard to firm,
reddish brown
4 Few or no Broken Variable Sloughing; Advanced decay at
stubs cubical, soft, base, sloughing
reddish to from upper bole,
dark brown fibrous to cubical,
soft, dark reddish
brown
5 None Broken Less than Gone Sloughing, cubical,
20% soft, dark brown,
OR fibrous, very
soft, dark reddish
brown, encased in
hardened shell
*
Characteristics are for Douglas-fir. Dead trees of other species may vary somewhat. Use
this only as a guide
5.21 UTILIZATION CLASS -- Code to identify cut trees that have been removed from the site.
When Collected: All removal trees (TREE STATUS = 3).
Field width: 1 digits
MQO: No errors, 100% of the time
Values:
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0 Not utilized - can still be found on the site.
1 Utilized cannot be found on site, assumed to have been removed.
5.22 HEIGHT TO DIAMETER (CORE OPTIONAL) -- Record this item when tree diameters are
not monumented. For those trees measured directly at of 4.5 ft. above the ground, leave
this item blank. If the diameter is not measured at 4.5 ft., record the actual height from
the ground, to the nearest 0.3 in., at which the diameter was measured for each tally tree,
1.0 in. DBH and larger, when the diameter is not measured at the standard height of 4.5
ft.. Leave this item blank for western woodland species measured for diameter at root
collar.
When Collected: All tally trees and tally saplings.
Field width: 3 digits
MQO: +/- 0.3 in, at least 90% of the time
Values:
5.23 PERCENT ROUGH CULL (CORE OPTIONAL) -- For each tally tree 5.0-inch DBH/DRC
and larger, record the percentage of sound dead cubic-foot volume, to the nearest 5
percent. When estimating volume loss (tree cull) only consider the cull on the
merchantable bole/portion of the tree. Refer to local defect guidelines as an aid in
determining cull volume for various damages, such as fire, frost crack, etc.
When Collected: All tally trees.
Field width: 2 digits
MQO: +/- 10%, at least 90% of the time
Values: 00 to 99
5.24 MISTLETOE CLASS (CORE OPTIONAL) -- Rate all live conifer species, except juniper
species, 1.0 in. and larger, for dwarf mistletoe (Arceuthobium spp.) infection. Use the
Hawksworth six-class rating system: divide the live crown into thirds, and rate each third
using the following scale:
When Collected: All tally trees.
Field width: 1 digit
MQO: +/- 1 class, at least 90% of the time
Values: 0 to 6
0 No visible infection
1 Light infection --
5. Site Tree selection criteria and species by region.
6. Number of trees required to achieve 50% stocking, by diameter.
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